In the past, metallic sealed double containers have been used as cooling devices for storing low-temperature heat sources such as a cooling medium in an inner container, or as heat storage devices for storing high-temperature heat sources in an inner container. In order to inhibit the transfer of heat from the inner container to the outer container, typical configurations that are often used involve providing an insulating material between the inner container and the outer container. In one configuration in which an insulating material is provided, heat-insulating effects are produced by maintaining a vacuum state between the inner container and outer container in a sealed double-container.
A superconductor cooling device (refer to patent document 1) and the like has been offered as a cooling device of such configuration, and a metallic vacuum double container (refer to patent document 2) and the like has been offered as a heat storage device.
With the invention described in patent document 1, the inner container and outer container are not constituted by a metallic material. Rather, the inner container and outer container are constituted by glass-fiber reinforced plastic. Thus, the bottomed tube-shaped body that constitutes the outer container and the outer container lid part are fixed using adhesive having epoxy resin as its primary component. In addition, the bottomed tube-shaped body that constitutes the inner container and the inner container lid part are fixed using an adhesive having epoxy resin as a primary component. Next, through-holes are formed in the lid part of the inner container and the lid part of the outer container, and a liquid nitrogen supply passage and nitrogen discharge passage that communicate with the internal space of the inner container respectively pass through these through-holes.
The liquid nitrogen supply passage and the nitrogen discharge passage have a double-wall configuration with an inner tube and outer tube, with foamed urethane inserted between the inner tube and outer tube. The inner container is fixed to the outer container with a fixing member interposed therebetween, and one end surface of the fixing member is fixed to the inner surface of the lid part of the outer container, whereas the other end surface is fixed to the outer surface of the lid part of the inner container. Fixing of the two end surfaces of the fixing members is achieved using an adhesive having epoxy resin as primary component.
The space between the inner container and the outer container is maintained in a substantially vacuum state. In addition, an activated carbon layer used for adsorption is provided on the outer circumferential surface of the inner container. A super-insulating layer for reflecting radiant heat is provided on the outer circumferential side of the activated carbon layer for adsorption. The super-insulating layer is a polyester resin film having an aluminum vapor deposition layer formed on one surface and a fibrous material such as paper formed on the other surface. A configuration is produced in which a polyester resin film is wound in innumerable layers on the outer circumferential side of the activated carbon layer for adsorption.
In the invention described in patent document 2, a double configuration is produced that comprises a metallic inner container and an outer container, with the space between the inner and outer containers being maintained in a vacuum state. A raised constriction part that is constricted towards the interior of the inner container is formed on the opening portion of the inner container. An inner end part of a mouth pipe is inserted and joined to the constriction part. An outer end part of the mouth pipe is joined to the opening part of the outer container. The opening part of the inner container is constituted by the mouth pipe.
A plug is inserted into the mouth pipe, producing a configuration in which the mouth pipe is stopped by the plug. A liquid outlet and liquid inlet that communicate with the internal space of the inner container are formed in the plug.